Patient characteristics and outcomes of a provincial prolonged-ventilation weaning centre: a retrospective cohort study.

BACKGROUND: Growing numbers of critically ill patients require prolonged mechanical ventilation and experience difficulty with weaning. Specialized centres may facilitate weaning through focused interprofessional expertise with an emphasis on rehabilitation.

OBJECTIVE: To characterize the population of a specialized prolonged-ventilation weaning centre (PWC) in Ontario, and to report weaning, mobility, discharge and survival outcomes.

METHODS: Data from consecutively admitted patients were retrospectively extracted from electronic and paper medical records by research staff and verified by the primary investigator.

RESULTS: From January 2004 to March 2011, 144 patients were admitted: 115 (80%) required ventilator weaning, and 29 (20%) required tracheostomy weaning or noninvasive ventilation. Intensive care unit length of stay before admission was a median 51 days (interquartile range [IQR] 35 to 86 days). Of the patients admitted for ventilator weaning, 76 of 115 (66% [95% CI 55% to 75%]) achieved a 24 h tracheostomy mask trial in a median of 15 days (IQR eight to 25 days). Weaning success, defined as no further ventilation for seven consecutive days, was achieved by 61 patients (53% [95% CI 44% to 62%]) in a median duration of 62 days (IQR 46 to 95 days) of ventilation, and 14 days (IQR nine to 29 days) after PWC admission. Seventeen patients died during admission. Of the 91 patients discharged from the PWC for one year, 43 (47.3% [95% CI 37.3% to 57.4%]) survived; of the 78 discharged for two years, 27 (34.6% [95% CI 25.0% to 45.7%]) were alive; of the 53 discharged for three years, 19 (35.9% [95% CI 24.3% to 49.3%]) were alive; and seven of 22 (31.8% [95% CI 16.4% to 52.7%]) survived to five years.

CONCLUSIONS: Weaning success was moderate despite a prolonged intensive care unit stay before admission, but was comparable with studies reporting weaning outcomes from centres in other countries. Few patients survived to five years.